Suggestion for HOT psi on NT01's for C7 Z51?
04-28-2016, 04:41 PM
#1
Pro
Thread Starter
Suggestion for HOT psi on NT01's for C7 Z51?
I'm still playing around with the pressure on the Nittos for the C7 and haven't figured out the best pressure yet. I'm coming from a Camaro ZL1 and only ran the NT01's twice on that car. Current front Camber is -1.5 front, -1.2 rear, 0.05 toe in on both the front and back (per GM). The C7 is stock other than Carbotech XP20 front, XP12 rear and DOT4 fluid.
Last event I had the front & rear tire pressure at the same psi, the Corvette had terrible oversteer and the back end felt very slippery. I've read conflicting reports that you should increase rear tire pressure (for spring rate) and then others say drop rear tire pressure (for contact patch). So I'm at a crossroads.
Last event I had the front & rear tire pressure at the same psi, the Corvette had terrible oversteer and the back end felt very slippery. I've read conflicting reports that you should increase rear tire pressure (for spring rate) and then others say drop rear tire pressure (for contact patch). So I'm at a crossroads.
Last edited by BaylorCorvette; 04-28-2016 at 05:40 PM.
05-01-2016, 12:04 PM
#2
Get a tire pyrometer and learn how to use it.
Remember, a tire is a like a spring. Drop a flat tire off a ladder and it justs flops over. Drop a tire with air pressure in it and it will bounce up.
So,,,, very old simple rule, stiff end slides first. More air pressure in a tire increases the spring rate,
All this is within the design pressures for the tire.
.more rear pressure, more rear sway bar= more oversteer. It's gets more complicated, but start here.
Of course , throttle control can play a part with high power and oversteer . Might want to check for that also. Squeeze the throttle open to help the tire hook up. Kinda like what traction control does.
Remember, a tire is a like a spring. Drop a flat tire off a ladder and it justs flops over. Drop a tire with air pressure in it and it will bounce up.
So,,,, very old simple rule, stiff end slides first. More air pressure in a tire increases the spring rate,
All this is within the design pressures for the tire.
.more rear pressure, more rear sway bar= more oversteer. It's gets more complicated, but start here.
Of course , throttle control can play a part with high power and oversteer . Might want to check for that also. Squeeze the throttle open to help the tire hook up. Kinda like what traction control does.
Last edited by Racer86; 05-01-2016 at 12:07 PM.
05-05-2016, 02:41 PM
#3
I'm still playing around with the pressure on the Nittos for the C7 and haven't figured out the best pressure yet. I'm coming from a Camaro ZL1 and only ran the NT01's twice on that car. Current front Camber is -1.5 front, -1.2 rear, 0.05 toe in on both the front and back (per GM). The C7 is stock other than Carbotech XP20 front, XP12 rear and DOT4 fluid.
Last event I had the front & rear tire pressure at the same psi, the Corvette had terrible oversteer and the back end felt very slippery. I've read conflicting reports that you should increase rear tire pressure (for spring rate) and then others say drop rear tire pressure (for contact patch). So I'm at a crossroads.
Last event I had the front & rear tire pressure at the same psi, the Corvette had terrible oversteer and the back end felt very slippery. I've read conflicting reports that you should increase rear tire pressure (for spring rate) and then others say drop rear tire pressure (for contact patch). So I'm at a crossroads.
08-28-2016, 01:44 AM
#4
Sr.Random input generator
This was back when I asked for my 2500 lbs Miata:
Tomorrow (It will be around 80 degrees F), I'll try 30F/29R PSI cold, and see where the temps get, shooting for 36-38 PSI. I am guessing those pressures will be a bit high, and I will adjust/bleed accordingly.
Thank you for contacting Nitto Tire.
For tire pressures, we've found the NT01 likes hot pressures in the high 30s. However, with your lighter car, we would suggest to target a slightly lower hot tire pressure. Your starting cold pressures would depend on how much your tire pressures grow on track.
We would recommend performing an initial heat cycle prior to hard competition use. Gradually bring the tires up to their optimal operating temperature, between 160 and 220 degrees F. Then gradually bring them down in temperature and let them sit overnight. They should be ready to go the next day. We'd also recommend a camber angle between -2.5 and -5.0 degrees.
Please keep in mind these are general guidelines for setting up your vehicle and the NT01s. The right setup for you would ultimately depend on what you feel most comfortable with.
For tire pressures, we've found the NT01 likes hot pressures in the high 30s. However, with your lighter car, we would suggest to target a slightly lower hot tire pressure. Your starting cold pressures would depend on how much your tire pressures grow on track.
We would recommend performing an initial heat cycle prior to hard competition use. Gradually bring the tires up to their optimal operating temperature, between 160 and 220 degrees F. Then gradually bring them down in temperature and let them sit overnight. They should be ready to go the next day. We'd also recommend a camber angle between -2.5 and -5.0 degrees.
Please keep in mind these are general guidelines for setting up your vehicle and the NT01s. The right setup for you would ultimately depend on what you feel most comfortable with.
Last edited by X25; 08-28-2016 at 01:55 AM.
08-28-2016, 03:46 PM
#5
Pro
I typically check both temp and pressure. On my 2800 lbs track car w/about 53f/47r weight distribution I have dialed NT01's to 36f/34r hot.
I check temp to see what the distribution is across the tire (using a Harbor Freight pyrometer). Some try to get even temp across, but that's way too conservative. You can allow the variation to go as high as 15 degrees across front, and 10 degrees across the rear. The distribution tells the story, since the cool down lap, and the drive to pit will drop the temp.
You should have higher temp on the inside than outside. If the center temp is lower or higher than the either side, that's when you know you are way off.
I'd imagine with C7's with heavier weight, equal distribution, you might start with 38 hot (28 cold) all around, and go from there.
Obviously front outside tire (right front with counterclockwise track, left front with clockwise) will be the hottest, but look for distribution of temp.
I check temp to see what the distribution is across the tire (using a Harbor Freight pyrometer). Some try to get even temp across, but that's way too conservative. You can allow the variation to go as high as 15 degrees across front, and 10 degrees across the rear. The distribution tells the story, since the cool down lap, and the drive to pit will drop the temp.
You should have higher temp on the inside than outside. If the center temp is lower or higher than the either side, that's when you know you are way off.
I'd imagine with C7's with heavier weight, equal distribution, you might start with 38 hot (28 cold) all around, and go from there.
Obviously front outside tire (right front with counterclockwise track, left front with clockwise) will be the hottest, but look for distribution of temp.
Last edited by Kamran; 08-29-2016 at 12:56 AM.